<!-- /*
 * @Author: RDSunday 
 * @Date: 2020-03-16 20:00:54 
 * @Last Modified by:   RDSunday 
 * @Last Modified time: 2020-03-16 20:00:54 
 */ -->
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .popup {
    position: relative;
    display: inline-block;
    cursor: pointer;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

/* The actual popup */
.popup .popuptext {
    visibility: hidden;
    width: 160px;
    background-color: #555;
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 8px 0;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    margin-left: -80px;
}

/* Popup arrow */
.popup .popuptext::after {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    margin-left: -5px;
    border-width: 5px;
    border-style: solid;
    /* 设置倒三角 底边和左右边设置透明不可见 */
    border-color: #555 transparent transparent transparent;
}

/* Toggle this class - hide and show the popup */
.popup .show {
    visibility: visible;
    -webkit-animation: fadeIn 1s;
    animation: fadeIn 1s;
}

/* Add animation (fade in the popup)
 @-webkit-keyframes fadeIn {
    from {opacity: 0;} 
    to {opacity: 1;}
}

@keyframes fadeIn {
    from {opacity: 0;}
    to {opacity:1 ;}
} */
    </style> 
</head>
<body style="text-align:center">
    <h2>弹窗</h2>
    
    <div class="popup" onclick="myFunction()">点我有弹窗!
        <span class="popuptext" id="myPopup">提示信息!</span>
</div>
<script>
    function myFunction() {
    var popup = document.getElementById("myPopup");
    popup.classList.toggle("show");
}
</script>
</body>
</html>